Blister packaging for liquid

ABSTRACT

A packaging is proposed, particularly a blister packaging, having at least one cavity for holding a liquid. The packaging comprises a capillary stop for the liquid which surrounds the cavity.

The present invention relates to a packaging, particularly blister packaging, having at least one cavity for holding a liquid, according to the preamble of claim 1.

The present invention relates to the admission of a liquid into a packaging, particularly a blister packaging. The liquid is admitted into a cavity in the packaging. The cavity is formed in particular by a blister. The following description is therefore directed to a blister pack or to a blister for holding a liquid, even if the present invention is not restricted to this but may also preferably be used in other liquid packaging.

The filling of one or more cavities with substances, solid objects or liquids is known, for example, from the field of so-called visual packaging or blister packs. Blister packs are used in various sectors and industrial fields and are provided with at least one cavity into which the contents to be packed therein are introduced. As a rule the contents of the cavity are visible from outside. However, the blister packs may also cover or encase the contents or the liquid contained therein in airtight or concealed manner.

A typical blister pack usually comprises two films which in turn may be made up of several layers of different or identical materials. The films are generally made of plastics and/or metal, e.g., aluminium, while other materials such as paper or the like may theoretically also be used, or used in addition. The two films are, in particular, a base layer or base film (support) and a cover layer or cover film (cover).

In the base film or support there may be one or more wells or depressions for holding the liquid, into which the liquid, particularly a pharmaceutical formulation, is introduced. The cover film or the cover is then placed on the base film or support and fixed or attached thereto, and this is done, for example, at the edges or in a connecting region, particularly in flatly abutting surface regions, preferably by adhesion, heat-sealing, welding or the like.

DE 103 43 668 A1 discloses a particularly leaktight blister pack for medicaments; the filling of the blister pack is not described in detail.

DE 20 2007 003 050 U1 discloses a blister pack for a liquid active substance. Here, the active substance is supposed to be released into the environment by diffusion. However, this is precisely what the packaging according to the invention sets out to prevent.

The present invention relates in particular to total filling of a cavity of packaging, particularly blister packaging, with a liquid. Particularly preferably the intention is to enable or assist filling without any gas or air bubbles. Total filling of this kind is necessary, for example, when a blister pack is fitted to a medical cartridge or arrangement (for example, a so-called biosensor) and the liquid introduced into the cavity of the blister pack, particularly provided with a reagent or a number of reagents, is supposed to initiate or permit a certain analytical reaction in the cartridge. The cartridge will then usually comprise a microfluidic system. To ensure that an analytical reaction to be performed by the liquid is not falsified or influenced, it may also be necessary for the liquid to be transferred to the cartridge with no gas or air bubbles after the cavity has been opened. This presupposes, among other things, that the cavity of the blister pack is itself completely filled with the liquid, i.e., with no gas or air bubbles. However, total filling of the cavity or of a blister with the liquid may also be desirable or necessary for other reasons, for example, with a view to ease of storage, resistance to changes in air pressure or the like.

The present invention is based on the problem of providing a packaging, particularly blister packaging, having a cavity for holding a liquid, in which total filling of the cavity, particularly a blister, with the liquid and/or leaktight sealing of the cavity is assisted or enabled.

The above problem is solved by a packaging according to claim 1. Advantageous further features are the subject of the sub-claims.

It is proposed that the packaging should comprise a capillary stop for the liquid. The capillary stop is arranged between the cavity and a connecting region or in the connecting region in which the base film or support on the one hand and the cover film or cover on the other hand are connected, or connectable, with one another. The capillary stop serves to prevent or at least limit or reduce the outflow or diffusion of the liquid from the cavity between the support and cover or the formation of a film of liquid - particularly in flatly abutting surface regions of the support and cover.

After the support or a depression in the support forming the cavity has been filled with the liquid, the depression is normally initially (loosely) covered with the cover or the cover film and then the cover is connected to the support, particularly in the flatly abutting surface regions, or in the connecting region. Tests have shown that the liquid can flow or diffuse into the gap between the cover and support, in the abutting surface regions, particularly by capillary forces, and indeed can flow into the intended connecting region or beyond it. As a result the cover and support may not be (sufficiently) well or totally connected in the connecting region in conventional packaging. The capillary stop ensures that the liquid is prevented from flowing (onwards) into the connecting region.

Accordingly, the proposed solution or the capillary stop assists with a secure and leaktight connection of the cover and support in the connecting region or in the connecting region on the outside adjacent to the capillary stop. Consequently, the proposed solution or the capillary stop assists with total filling of the packaging or cavity with liquid. The capillary stop in fact also ensures that after filling, liquid cannot flow out of the cavity in an undesirable manner, particularly as a result of the capillary effect of the abutting surface regions of the cover and support, before the packaging or the cavity or blister is finally sealed.

By the term “capillary stop” is generally meant, in particular, according to the present invention, a means that prevents onward flow of the liquid by capillary forces. Preferably, the capillary stop is formed by an, in particular, abrupt enlargement of the cross-section, through which the liquid is to flow. Particularly preferably, the capillary stop is formed for this purpose by a depression in the support and/or in the cover. The depression is more particularly in the form of a groove, channel and/or ring. This ensures ease of production, particularly using the tools, machines and/or processes that are conventionally utilised precisely for blister packaging.

The capillary stop preferably surrounds the cavity circumferentially and/or concentrically. This allows a simple and/or compact design and/or prevents unwanted penetration of liquid from the cavity into an outwardly adjacent region.

Further advantages, features, properties and aspects of the present invention will be apparent from the claims and the following description of a preferred embodiment by reference to the drawings, wherein:

FIG. 1 shows a diagrammatic section through packaging according to the prior art; and

FIG. 2 shows a diagrammatic section through proposed packaging.

In the Figures the same reference numerals have been used for identical or similar parts where corresponding or comparable properties and advantages are achieved, even if the description is not repeated.

FIG. 1 shows in diagrammatic section a packaging 1 fundamentally known from the prior art, having at least one cavity 2 for holding a liquid 3.

The packaging 1 seals in the liquid 3 preferably at least substantially in fluidtight and/or gastight manner.

The packaging 1 is embodied in particular as a blister pack. The cavity 2 is formed in particular by a blister of the packaging 1 or blister pack.

The liquid 3 is, in particular, an investigation liquid, a washing liquid, a reaction liquid, a solvent or the like, particularly preferably for use in a microfluidic system for determining an analyte or value and/or for investigating, in particular, a preferably biological sample or the like.

The packaging 1 comprises a support 4 and an associated cover 5.

The support 4 is, in particular, an at least substantially flat or planar element and/or flat material and/or a base layer or base film or the like.

The support 4 may be relatively rigid or else flexible and/or deformable at least in some areas. Preferably, the support 4 has relatively great rigidity or strength in its main direction or plane of extent.

In the embodiment shown, the support 4 is preferably more rigid or stiff in construction than the cover 5 and/or sufficiently rigid to at least substantially or primarily determine the deformation of the packaging 1.

The cover 5 is preferably an at least substantially flat or planar and/or smooth element or flat material and/or a cover layer or cover film, particularly preferably for flatly covering the associated support 4.

Preferably, the support 4 and/or the cover 5 is or are embodied as a film and/or made of film, plastics, metal and/or a composite material containing plastics and/or metal, in particular.

The support 4 and the cover 5 may theoretically be made from the same material. In the embodiment shown, the support 4 and the cover 5 are, however, preferably made from different materials.

The cover 5 is preferably of flexible and/or deformable construction and is in particular capable of being opened, for example by tearing open, pressing in, piercing or the like, particularly preferably in order to take out or dispense the liquid 3. Alternatively or additionally, the support 4 may also be openable in corresponding manner.

At least one cavity 2 for holding the liquid 3 is formed between the support 4 and the cover 5. Particularly preferably, a number of cavities 2 are formed.

In particular the packaging 1 or the support 4 and/or cover 5 may particularly preferably comprise a strip of continuous material or the like. The continuous material can then be divided or separated into individual packages 1 each having at least one cavity 2 for holding the liquid 3, before or preferably after the introduction of the liquid 3, as required. The following description will detail only the preferred construction of a cavity 2, even though the continuous material or the packaging 1 may comprise several such cavities 2, optionally also of different sizes and/or containing different liquids 3.

In order to form the cavity 2, a depression or concavity is preferably formed in the support 4 and/or cover 5, preferably only in the support 4, in the embodiment shown, as illustrated in FIG. 1. The depression or concavity is particularly in the form of a well. The depression or cavity 2 is produced in particular by thermoforming and/or deep-drawing, in this case of the support 4.

After the introduction of the liquid 3 into the depression or concavity or cavity 2—in the support 4 according to the embodiment shown—the packaging 1 or cavity 2 is closed or sealed. To do this the cover 5 is placed on top and at least partly attached to the support 4 in a connecting region 6. The connecting region 6 is formed in particular in the region of flatly abutting surface regions of the support 4 and cover 5. The connecting region 6 adjoins the cavity 2, particularly laterally and/or circumferentially. For example, the connecting region may surround the cavity 2 in an annular configuration.

The connecting region 6 or, in the case of a plurality of cavities, the plurality of connecting regions 6, is or are preferably located in a plane and/or in the main plane of extent 10 and/or on a flat side of the packaging, the support and/or cover 5. In particular, the connecting region 6 surrounds the cavity 2 in question in a circumferential and/or annular manner.

The connecting of the support 4 and cover 5 is preferably carried out by heat-sealing, welding, adhesion and/or any other suitable method.

The support 4 and the cover 5 are connected or connectable with one another in the connecting region 6 at least substantially in fluidtight manner, in particular in at least substantially gastight, continuous, annular and/or circumferential manner.

FIG. 1 shows, in a highly diagrammatic, unrealistic representation, the packaging 1 after the introduction of the liquid 3 and with the cover 5 already loosely placed on the support 4. FIG. 1 diagrammatically shows that the liquid 3 can penetrate into the connecting region 6, particularly from the cavity 2, and/or may remain in the connecting region 6, for example, when the cavity 2 is being filled with liquid. This film of liquid which extends into the connecting region 6 and/or at least partly covers the latter, may impede or even prevent the secure and/or leaktight connection of the support 4 and cover 5 in the connecting region 6 or hermetic sealing of the cavity 2. In particular, an unwanted cushion of liquid may form in the connecting region 6 or between the support 4 and cover 5. Tests have shown that in a packaging 1 of this kind, a substantial loss of liquid often occurs particularly in the first few days after filling and sealing of the packaging 1 or after placing it in storage. This may be explained by the fact that liquid 3 is enclosed in the connecting plane or in the connecting region 6 and as a result of reduced adhesion it may diffuse out or escape over time.

FIG. 2 shows, in a diagrammatic section corresponding to FIG. 1, the packaging 1 provided with a stop structure as proposed. The packaging 1 differs from the packaging shown and described in FIG. 1 particularly only by the formation of a structure for catching or stopping or impeding the liquid 3 in the connecting plane or connecting region 6. This structure is particularly preferably formed by a capillary stop 7 in the embodiment shown. However, other structures may theoretically also be used.

The term “capillary stop” is preferably to be understood in the sense stated hereinbefore in connection with the general description of the invention. However, the term “capillary stop” should preferably also be understood as another structure for stopping or at least holding back liquid 3. It is, in particular, a structure obtained by deformation and/or geometric shaping.

The capillary stop 7 prevents the liquid 3 or liquid film from being able to flow or run (further) into the connecting region 6.

The capillary stop 7 particularly prevents liquid 3 from moving beyond the capillary stop 7 into the outer region or connecting region 6 during the closure phase or closing of the packaging 1 or cavity 2—i.e., of the blister formed by the cavity 2 in the embodiment shown—and adversely affecting the adhesion and/or the uniform or leaktight connection of the support 4 and cover 5 there. Moreover, the contamination of the environment is prevented or at least minimised by stopping liquid 3 from escaping. Moreover, the inclusion of air or gas in the cavity 2 is reduced or ideally prevented altogether.

The capillary stop 7 is formed in particular by a recess 8 in the support 4 and/or cover 5—in the support 4 in the embodiment shown. Particularly preferably, the depression 8, like the cavity 2, is produced by deep-drawing and/or thermoforming.

The capillary stop 7 or the depression 8 surrounds the cavity 2 preferably circumferentially, annularly and/or concentrically.

The capillary stop 7 or the depression 8 is preferably embodied as a groove, channel and/or ring.

The capillary stop 7 or the depression 8 preferably has a depth of at least 0.3 mm, particularly substantially 0.5 mm or more, and/or a width of at least 1 mm, particularly substantially 2 mm or more.

The capillary stop 7 is preferably arranged between the connecting region 6 and the cavity 2. Alternatively, however, the capillary stop 7 may also be arranged in the connecting region 6.

The capillary stop 7 is preferably arranged in the connecting plane 10 of the packaging 2 or in or on the flat side of the support 4.

The capillary stop 7 is preferably arranged in the region of flatly abutting surface regions of the support 4 and cover 5. Between the capillary stop 7 and the cavity is preferably arranged or formed an annular region 9 that laterally adjoins the cavity 2. The capillary stop 7 is preferably spaced from the cavity 2 on all sides, uniformly and/or radially.

Preferably, the connecting region 6, the capillary stop 7 and/or the annular region 9 are located at least substantially in a plane or in the main plane of extent 10 of the packaging 1.

The spacing of the capillary stop 7 from the cavity 2 or the width of the annular region 6 is preferably at least 1 mm, particularly substantially 2 mm more.

If required, a plurality of capillary stops 7 may also be arranged one behind the other and/or concentrically.

In the closed state the cover 5 may either cover the capillary stop 7 or its depression 8 smoothly or in planar fashion and/or it may be deformed into the capillary stop 7 or its depression 8.

In the embodiment shown the capillary stop 7 is arranged (radially) within the connecting region 6.

In the embodiment shown the connecting region 6 preferably directly adjoins the capillary stop 7 radially or externally. However, the connecting region 6 may also be arranged at a spacing from the capillary stop 7 or vice versa.

Alternatively, the capillary stop 7 may also be arranged in the connecting region 6. The capillary stop 7 then ensures that at least in the region of the connecting region 6, which is on the side of the capillary stop 7 remote from the cavity, a good connection is made possible, particularly as the occurrence of a liquid film or liquid cushion or liquid 3 is prevented or at least minimised there.

List of Reference Numerals

1 packaging

2 cavity

3 liquid

4 support

5 cover

6 connecting region

7 capillary stop

8 depression

9 annular region

10 plane 

1. Packaging (1) having at least one cavity (2) for holding a liquid (3), the packaging (1) comprising a support (4) and a cover (5), between which the cavity (2) is formed and which are connected or connectable with one another in a connecting region (6) surrounding the cavity (2), characterised in that the packaging (1) comprises a capillary stop (7) for the liquid (2), which is arranged between the cavity (2) and the connecting region (6) or in the connecting region (6).
 2. Packaging according to claim 1, characterised in that the capillary stop (7) surrounds the cavity (2) circumferentially, annularly or concentrically or a combination thereof.
 3. Packaging according to claim 2, characterised in that the capillary stop (7) is formed by a depression (8) in the support (4) or the cover (5).
 4. Packaging according to claim 3, characterised in that the depression (8) is embodied as a groove, channel or ring or a combination thereof.
 5. Packaging according to claim 3, characterised in that the depression (8) has a depth of at least 0.3 mm, and a width of at least 1 mm.
 6. Packaging according to claim 1, characterised in that an annular region (9) laterally adjoining the cavity (2) is arranged or formed between the capillary stop (7) and the cavity (2).
 7. Packaging according to claim 6, characterised in that the connecting region (6) and the annular region (9) are located at least substantially in one plane (10).
 8. Packaging according to claim 1, characterised in that the connecting region (6) and the capillary stop (7) are located at least substantially in one plane (10).
 9. Packaging according to claim 1, characterised in that the connecting region (6) is of at least substantially planar configuration.
 10. Packaging according to claim 1, characterised in that the support (4) and the cover (5) are connected or connectable to one another in the connecting region (6) in at least substantially fluidtight, gastight, continuous, annular or circumferential manner or a combination thereof.
 11. Packaging according to claim 1, characterised in that the support (4) and the cover (5) are connected or connectable to one another in the connecting region (6) by adhesion, heat-sealing or welding.
 12. Packaging according to claim 1, characterised in that the support (4) is deep-drawn or thermoformed in parts to form the cavity (2) or the capillary stop (7).
 13. Packaging according to claim 1, characterised in that the support (4) is made from plastics, film or a composite material or a combination thereof.
 14. Packaging according to claim 1, characterised in that the cover (5) is embodied to be at least substantially flat or smooth or a combination thereof.
 15. Packaging according to claim 1, characterised in that the cover (5) is made from plastics, film or a composite material or a combination thereof. 